Design and rational of the OPTIMA Study: Retreatment or Step-Up Therapy with Omalizumab in Patients with Chronic Idiopathic/Spontaneous Urticaria (CIU/CSU). J of Skin [Internet]. 2017 Oct. 27 [cited 2025 Apr. 19];1(3.1):s125. Available from: https://skin.dermsquared.com/skin/article/view/184